# RapidEye 4

> decommissioned Earth observation satellite

**Wikidata**: [Q111496954](https://www.wikidata.org/wiki/Q111496954)  
**Source**: https://4ort.xyz/entity/rapideye-4

## Summary
RapidEye 4 was a decommissioned Earth observation satellite, part of the RapidEye constellation operated by Planet Labs. Launched in 2008, it was designed to capture high-resolution imagery for environmental monitoring, agriculture, and urban planning. The constellation was retired in 2020 after over a decade of service.

## Key Facts
- **Class**: Earth observation satellite
- **Part of**: RapidEye constellation (operated by RapidEye AG, BlackBridge, and Planet Labs)
- **Launch date**: August 29, 2008, at 07:15:58 UTC from Baikonur Cosmodrome
- **Launch vehicle**: Dnepr rocket
- **Mass**: 150 kg (launch weight)
- **Orbit**: Sun-synchronous orbit
- **Manufacturer**: MDA Space (general contractor), Surrey Satellite Technology (spacecraft bus), Jena-Optronik (payload)
- **Country of origin**: Canada
- **Decommissioned**: March 2020
- **Aliases**: Choros

## FAQs
### Q: What was the purpose of RapidEye 4?
A: RapidEye 4 was part of a constellation of Earth observation satellites designed to capture high-resolution imagery for environmental monitoring, agriculture, and urban planning. The constellation provided daily revisit capabilities for commercial and scientific use.

### Q: Who operated RapidEye 4?
A: RapidEye 4 was operated by RapidEye AG from 2008 to 2013, then by BlackBridge until 2015, and finally by Planet Labs until its retirement in 2020.

### Q: How was RapidEye 4 launched?
A: RapidEye 4 was launched on August 29, 2008, aboard a Dnepr rocket from Baikonur Cosmodrome Site 109. It was part of a multi-satellite launch, including RapidEye 1, 2, and 3.

### Q: What was the significance of the RapidEye constellation?
A: The RapidEye constellation was notable for its high-resolution imagery and daily revisit capabilities, making it valuable for environmental monitoring, agriculture, and disaster response. Its retirement in 2020 marked the end of an era in commercial Earth observation.

### Q: What was the spacecraft bus used for RapidEye 4?
A: RapidEye 4 used the SSTL-150 spacecraft bus, developed by Surrey Satellite Technology. The payload was provided by Jena-Optronik.

## Why It Matters
RapidEye 4 was part of a pioneering constellation of Earth observation satellites that revolutionized commercial remote sensing. Launched in 2008, the constellation provided high-resolution imagery with daily revisit capabilities, making it invaluable for environmental monitoring, agriculture, and urban planning. Operated by RapidEye AG, BlackBridge, and Planet Labs, the satellites supported applications ranging from crop health assessment to disaster response. The constellation’s retirement in 2020 marked the end of an era in commercial Earth observation, as newer satellites with advanced capabilities took over. RapidEye 4’s legacy lies in its contribution to the development of high-resolution commercial remote sensing, setting a standard for future satellite constellations.

## Notable For
- **First commercial constellation with daily revisit**: RapidEye 4 was part of the first commercial constellation capable of daily Earth observation, enabling frequent monitoring of dynamic processes.
- **High-resolution imagery**: The constellation provided imagery with a resolution of up to 6.5 meters, making it suitable for detailed environmental and agricultural analysis.
- **Multi-sensor payload**: RapidEye 4 featured a payload designed by Jena-Optronik, contributing to the constellation’s ability to capture multispectral imagery.
- **Operational lifespan**: The constellation operated for over a decade, from 2008 to 2020, demonstrating the reliability and longevity of its design.
- **Transition to Planet Labs**: The constellation’s transfer to Planet Labs in 2015 highlighted the evolving landscape of commercial Earth observation, with Planet Labs later expanding into larger constellations like SkySat and Flock.

## Body
### Overview
RapidEye 4 was a decommissioned Earth observation satellite, part of the RapidEye constellation operated by Planet Labs. Launched in 2008, it was designed to capture high-resolution imagery for environmental monitoring, agriculture, and urban planning. The constellation was retired in 2020 after over a decade of service.

### Launch and Design
RapidEye 4 was launched on August 29, 2008, aboard a Dnepr rocket from Baikonur Cosmodrome Site 109. It was part of a multi-satellite launch, including RapidEye 1, 2, and 3. The satellite had a launch mass of 150 kg and used the SSTL-150 spacecraft bus, developed by Surrey Satellite Technology. The payload was provided by Jena-Optronik, contributing to the constellation’s ability to capture multispectral imagery.

### Operation and Ownership
RapidEye 4 was operated by RapidEye AG from 2008 to 2013, then by BlackBridge until 2015, and finally by Planet Labs until its retirement in 2020. The constellation was notable for its high-resolution imagery and daily revisit capabilities, making it valuable for environmental monitoring, agriculture, and disaster response.

### Significance
The RapidEye constellation was a pioneer in commercial Earth observation, providing high-resolution imagery with daily revisit capabilities. Its retirement in 2020 marked the end of an era in commercial remote sensing, as newer satellites with advanced capabilities took over. RapidEye 4’s legacy lies in its contribution to the development of high-resolution commercial remote sensing, setting a standard for future satellite constellations.

## References

1. [Source](https://space.skyrocket.de/doc_sdat/rapideye-1.htm)
2. [Source](https://www.eoportal.org/satellite-missions/rapideye)
3. Jonathan's Space Report
4. [Source](https://www.planet.com/pulse/rapideye-constellation-to-be-retired-in-2020/)
5. [Source](https://www.planet.com/pulse/historic-rapideye-constellation-captures-last-light/)